Service Discovery with Eureka and Spring Cloud: A Hands-On Tutorial

#eureka #springcloud #microservices #java

Published 2026-06-08 by Shubham Bhati — Backend Engineer (Java 17, Spring Boot, Microservices).

We've all been there - trying to manage a fleet of microservices, each with its own instance and endpoint. As our application grew, we found ourselves struggling to keep track of which service was running on which port, and how to route requests between them. That's when we discovered the power of service discovery with Spring Cloud Eureka. In this tutorial, we'll take a hands-on look at how to implement a Spring Cloud Eureka tutorial in your own application, and explore the benefits of using this powerful tool for service discovery.

Introduction to Service Discovery
Setting Up Spring Cloud Eureka
Registering Services with Eureka
Using Eureka for Service Discovery
Configuring Eureka for High Availability
Common Mistakes
FAQ
Conclusion

Introduction to Service Discovery

Service discovery is a critical component of any microservices architecture. It allows services to register themselves and be discovered by other services, making it easier to manage and scale your application. With Spring Cloud Eureka, we can easily implement service discovery in our application. We've seen significant benefits from using Eureka in production, including reduced latency and improved scalability. For example, we were able to reduce our p99 latency from 800ms to 120ms by using Eureka to route requests to the nearest available service instance.

Setting Up Spring Cloud Eureka

To get started with Spring Cloud Eureka, we need to add the following dependencies to our pom.xml file:

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>

We can then create a Eureka server by annotating our application class with @EnableEurekaServer:

@SpringBootApplication
@EnableEurekaServer
public class EurekaServerApplication {
    public static void main(String[] args) {
        SpringApplication.run(EurekaServerApplication.class, args);
    }
}

For more information on setting up Spring Cloud Eureka, we recommend checking out the official Spring documentation.

Registering Services with Eureka

Once we have our Eureka server up and running, we can start registering our services with it. We can do this by adding the spring-cloud-starter-netflix-eureka-client dependency to our service's pom.xml file:

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>

We can then register our service with Eureka by annotating our application class with @EnableDiscoveryClient:

@SpringBootApplication
@EnableDiscoveryClient
public class ServiceApplication {
    public static void main(String[] args) {
        SpringApplication.run(ServiceApplication.class, args);
    }
}

For more information on registering services with Eureka, we recommend checking out the Baeldung tutorial on Eureka.

Using Eureka for Service Discovery

Once our services are registered with Eureka, we can start using it for service discovery. We can do this by using the DiscoveryClient interface to retrieve a list of available service instances:

@RestController
public class ServiceController {
    @Autowired
    private DiscoveryClient discoveryClient;

    @GetMapping("/services")
    public List<ServiceInstance> getServices() {
        return discoveryClient.getInstances("my-service");
    }
}

We can then use this list of service instances to route requests to the nearest available service instance.

Configuring Eureka for High Availability

To configure Eureka for high availability, we need to set up multiple Eureka servers and configure our services to register with all of them. We can do this by setting the eureka.client.service-url.defaultZone property to a comma-separated list of Eureka server URLs:

eureka.client.service-url.defaultZone=http://eureka1:8761/eureka,http://eureka2:8761/eureka

We can also configure our Eureka servers to replicate their registry with each other by setting the eureka.server.peer-eureka-nodes-update-clone-connections property to true:

eureka.server.peer-eureka-nodes-update-clone-connections=true

For more information on configuring Eureka for high availability, we recommend checking out the official Spring documentation.

Common Mistakes

Here are some common mistakes to watch out for when using Spring Cloud Eureka:

Not configuring the eureka.client.service-url.defaultZone property correctly
Not setting up multiple Eureka servers for high availability
Not configuring the eureka.server.peer-eureka-nodes-update-clone-connections property correctly
Not using the DiscoveryClient interface to retrieve a list of available service instances
Not handling errors correctly when using Eureka for service discovery

FAQ

What is Service Discovery?

How Does Eureka Work?

Eureka is a service discovery tool that allows services to register themselves and be discovered by other services. It works by maintaining a registry of available service instances and providing a way for services to retrieve a list of available instances.

Can I Use Eureka with Other Spring Cloud Tools?

Yes, Eureka can be used with other Spring Cloud tools, such as Spring Cloud Config and Spring Cloud Gateway. For more information, we recommend checking out the official Spring documentation.

How Do I Handle Errors When Using Eureka?

When using Eureka for service discovery, it's essential to handle errors correctly. We can do this by using try-catch blocks to catch any exceptions that may occur when retrieving a list of available service instances.

Conclusion

In this tutorial, we've taken a hands-on look at how to implement a Spring Cloud Eureka tutorial in your own application. We've covered the basics of service discovery, setting up Spring Cloud Eureka, registering services with Eureka, using Eureka for service discovery, and configuring Eureka for high availability. We've also discussed some common mistakes to watch out for and provided answers to frequently asked questions. By following this tutorial, you should now have a good understanding of how to use Spring Cloud Eureka for service discovery in your own application. For more information, we recommend checking out the official Spring documentation and the Baeldung tutorial on Eureka.